The present invention relates to an electrical junction box such as a fuse box, and more particularly to an electrical junction device having a terminal receiving chamber for receiving a joint terminal member formed with a conductive common base and a plurality of tab terminals extending from the common base.
In an electrical junction device such as a fuse box for connecting a plurality of terminals with each other, a group of the terminals has the same potential. Such terminals having the same potential are formed from a joint terminal member formed with a common base and a plurality of comb-like tab terminals extending from the common base.
FIG. 8 shows a conventional electrical junction device using such a joint terminal member. Referring to FIG. 8, reference numeral 1 designates an electrical insulating housing having a plurality of terminal receiving chambers 2 partitioned by a plurality of partition walls 3. A joint terminal member 4 is adapted to be inserted into the terminal receiving chambers 2 from a lower side of the housing 1 and locked in the terminal receiving chambers 2. The joint terminal member 4 is formed with a common base 4a and a plurality of tab terminals 4b extending upwardly from the common base 4a. The number of the tab terminals 4b corresponds to the number of the terminal receiving chambers 2. When the joint terminal member 4 is inserted and locked in the housing 1, the common base 4a of the joint terminal member 4 is inserted between an outer wall 1a of the housing 1 and a connecting portion 5 of the housing 1 so as to align a bolt hole 4c formed through the common base 4a with a female threaded hole 5a formed in the connecting portion 5. Then, a bolt hole 6a of a terminal 6 of an external wire is aligned with the bolt hole 4c of the common base 4a, and a bolt 7 is inserted through the bolt holes 6a and 4c into the female threaded hole 5a, thus connecting the terminal 6 to the joint terminal member 4 by fastening the bolt 7. Further, the joint terminal member 4 is formed with a plurality of lock holes 4d corresponding to the tab terminals 4b. As shown in FIG. 9, a lance 8 is formed in each of the terminal receiving chambers 2, so that a locking end of the lance 8 may be engaged with the corresponding lock hole 4d of the joint terminal member 4 when the joint terminal member 4 is inserted into the housing 1.
On the other hand, a plurality of independent male terminals 9 are adapted to be inserted into the terminal receiving chambers 2 from the lower side of the housing 1 and locked in the terminal receiving chambers 2 under the condition where the male terminals 9 are opposed to the tab terminals 4b, and are electrically insulated to tab terminals 4b. Electrical wires (not shown) from electrical parts are connected to lower ends of the male terminals 9.
A fusible link 11 having female terminals as mating terminals 10 are connected to each tab terminal 4b and each male terminal 9 from an upper side of the housing 1. Thus, an electrical junction device A is constructed.
In the above-mentioned electrical junction device A, the joint terminal member 4 is inserted into the housing 1 from the lower side thereof, and the terminal 6 of the external wire is mounted from a side surface of the housing 1. Accordingly, after mounting the electrical junction device A at a given position in a vehicle or the like, the terminal 6 cannot be connected unless a sufficient working space around the electrical junction device A is ensured. Normally, since such a working space cannot be ensured, the timeframe during which terminal 6 can be mounted is actually limited.
Furthermore, as an insert direction of the mating terminals 10 of the fusible link 11 is the same as a detachment direction of the joint terminal member 4, there is a possibility that the joint terminal member 4 is detached under a depression force applied from the fusible link 11 upon insertion thereof. To eliminate such a problem, the lance 8 needs to be formed in each of the terminal receiving chambers 2 to prevent easy detachment of the joint terminal member 4. As a result, the structure of the housing 1 becomes complex.